In the process of a lot of fine tuning on this old boat we bought. I've been looking around in the engine rooms, and thinking about bilge pumps. And what would happen if I had a big hole knocked in the boat in that area, or a shaft/stuffing issue. These old engines are so simple, like all basic diesels, they would keep running no matter if the surrounding electrical stuff got shorted. But they would probably stop pretty quickly when the water level got up to the intake/air cleaner.

The batteries and alternator are above the level of the air intakes on my engines. So, if I could keep the engines running to keep the batteries charged and not shorted so the bilge pumps would keep running , I could probably keep going a long time.

It would be very easy for me to add some dryer hose or similar up to the vents several feet above the air intake for the engine. Does anyone do this? THey do it for Land ROvers, why not boats?

Seems that there are some times when keeping the engines going would be the only way to keep the water level low enough to prevent everything from shorting and stopping the bilge pumps.

Wonder if anyone has come up with an engine belt driven bilge pump for engine rooms?

I added about a 3' length of wet exhaust hose not "dryer duct", to the intake of our 107. It does not have much rise but it did move the inlet over to an area that makes the engine noise less noticeable. I added an air filter also. It is high enough that some of the sole would be a foot under water before it flooded the engine.
A "T" with a screen in your salt water intake is not an uncommon route to take with your pump idea.

Funny, there was a discussion about this just last week on Click n Clack (Car Talk Radio)!

The caller asked about this but mentioned that since she was in Africa and had to drive through a lot of deep water, the water depth interfered with the fan belt on the radiator!

Just one of those design "issues" the land Rover engineers seemed to have forgotten.

Their answer: don't worry about it, since the heat transfer of water is higher than air, the radiator will continue to work, but you should consider finding a way to stop the fan since, as the caller noted, it hit the radiator.

Location: Northern British Columbia, part of the time in Prince Rupert and part of the time on Moresby Island.

Boat: 50-ft steel Ketch

Posts: 1,885

Re: snorkels for diesels?

Quote:

It would be very easy for me to add some dryer hose or similar up to the vents several feet above the air intake for the engine. Does anyone do this? THey do it for Land ROvers, why not boats?

One of the problems you might run into is water being sucked into your air intake if waves break over the air intake vents in heavy seas. Normally, water entering the vents goes into the bilges, but connecting a hose from the engine intake to the vent will direct it directly to the engine.

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'Tis evening on the moorland free,The starlit wave is still: Home is the sailor from the sea, The hunter from the hill.

Good point. Maybe just extending the air intake upwards a foot or two would be easy and make some sense. Of course would have to make it all water tight for it to do any good in an extreme situation. Interesting comment on the noise. I didn't realize that much noise came out through the intake manifold, if I understand correctly.

If you are going through the trouble incase of rapid water ingress, I would say go all the way and get a serious dewatering system installed. The electric bilges aren't going to do a lot in the type of situation you are talking about. I would look at jabsco engine driven pumps or these drive shaft driven pumps Fast Flow Emergency Bilge Pump. These would largely benefit an engine with a snorkel and will actually remove a lot of water in the process.

Did this on our engine years ago after rebuilding it.Got fresh cooler air from aft lazzarette. And noise reduction. You can see the blue hose attached to the air intake.I was not worried about high water. That would be a whole other set of problems.

That's interesting. I've been running the engines without the air cleaner elements in, anyhow. I don't see that they're doing anything other than restricting the engine from being able to breathe. There's really not a dust or dirt problem anywhere near them. And they would only keep out stones and twig sized stuff anyhow, Not dust. I'm guessing this might be a source of a lot of mechanical noise, from what you guys are telling me. Makes sense.

I just bought a gallon of the Noxudol stuff to try to reduce engine noise, and this will become a part of that effort.

Remember flipping the lid on the airfliter of the older cars back in the 70's or so, how they made that deep, cool sound when you floored them? Well that was intake noise.
Drawing air from the Lazarette seems to be a good idea, but if you do that, you may want a bilge blower pulling fumes, smells and heat out of the engine compartment if you don't already have one as the engine normally does that through the intake

Also a good point about the starter cable, which is the lowest critical point on the diesels. I have a switch high on the bulkhead I can reach from above that isolates the batteries from the engine, if I remember to get to it when the water is just below the starter. Then at least I could continue to run the bilges until the batteries shorted. They're two feet higher than the starter.

Being able to run the pumps for another thirty minutes might make the difference. I would assume the most likely scenario for us to knock a hole that big in the boat is coming through the reefs here, meaning we would be in sight of land. Hitting reefs is notoriously hard on boats.